<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="./js/jquery-3.6.0.js"></script>
  </head>
  <body>
    <ul>
      <li>data</li>
      <li id="data">data</li>
      <li>data</li>
      <li class="c1">data</li>
      <li class="c1">data</li>
    </ul>

    <p class="c1">ppppppppppp</p>
    <p>xxxxxxxxxxx</p>
  </body>
</html>
<script>
  //id  = document.getElementById("data")
  $('#data').css('color', 'red')
  //class
  $('.c1').css('font-size', '40px')
  //标签
  $("li").css('color', 'blue')
  //并集 or
  $("#data,.c1").css('color', 'yellow');
  //交集 and
  $('li.c1').css('font-size', '60px')
  //通配
  $("*").css('font-size', '60px')
</script>
